Groceries and other goods are packed in bags at checkout counters, and plastic has become a common material for making such bags. A style of bag known as a T-shirt bag is frequently used, which has the appearance of a sleeveless shirt. Many improvements have been made in this art, and the bags of today, as compared to bags of the past, can be filled faster by checkout clerks, open wider and support more weight.
U.S. Pat. No. 5,188,235, issued to Pierce et al., discloses a bag with handles and mounting tabs disposed between the handles, where the handles and the mounting tabs have apertures for receiving the arm or hook of a dispensing rack. A pack of bags are mounted on the dispensing rack, and the mounting tabs are adapted to sever so that no portion of the bag remains on the rack when the bag is removed. This type of bag has become known as a tabless bag, and the patent further discloses a self-opening feature for the bags in a bag pack. Bags within a bag pack have means releasably bonding the individual mounting tabs to one another so that as one bag is removed, the next adjacent bag is opened because the rear wall of the first bag is releasably bonded to the front wall of the next adjacent bag. The tabless and self-opening features are believed to enhance the productivity of a checkout clerk.
U.S. Pat. No. 4,165,832, issued to Kuklies et al., reissued as Re. 34,019, discloses a bag of the type that leaves a tab on a dispensing rack as the bag is removed from the rack. This type of bag is known as a “tabbed” bag. A tabbed bag has a mounting tab, and a perforated line is provided along the base of the mounting tab. The tab tears away along the perforated line as the bag is removed from the rack, leaving the tab on the rack. Tearing the bag away from the tab results in nicks or small tears along a mouth portion of the bag. These nicks and small tears make the bags susceptible to a rip or tear emanating from one of the nicks or small tears along the mouth portion of the bag. Kuklies et al. provide a stress relief notch to eliminate the concentration of stress forces in those areas of the bag mouth that are especially susceptible to ripping, tearing and splitting. A stress relief notch is formed by cutting a notch in the bag mouth area between a lower portion of a handle and the mounting tab, leaving an edge between the lower portion of the handle and the mounting tab having an arcuate shape.
U.S. Pat. No. 4,759,639, issued to DeMatteis et al., addresses the vulnerability of a side gusset panel to ripping or tearing. Front and rear bag walls are joined together by side panels, which are folded inwardly, forming side gusset panels. The side gusset panels have a top edge and a longitudinal center crease. The top edge rises in the vicinity of the center crease to form a stress transfer tip, which functions to transfer stress away from the center crease at the top edge, making the top edge of the side gusset panel less likely to rip or tear.
Although there have been many improvements in plastic bags, further refinements and improvements can further improve the productivity of sales clerks while making the bags more durable and cost effective.